MSG Viewer

Natively, you cannot, and this is not a fault in your setup. A .msg is written by Outlook for Windows in a Microsoft container format, and Apple Mail, Gmail, Android and every mobile client read mail as MIME instead, so the file is meaningless to them. The options are to open it in Outlook on Windows, to install a dedicated reader, or to use a page like this one that parses the container in the browser. The browser route is the only one that works identically on a Mac, a phone and a locked-down work laptop, because it installs nothing.

Because .msg is a dump of Outlook's own internal representation of an item rather than an interchange format. Mail on the wire is MIME, which is what an .eml holds: readable headers followed by encoded parts. Outlook instead stores a message as a compound file, the same container used by an old .doc, holding hundreds of numbered MAPI properties. That preserves things MIME has no place for, such as Outlook categories, flags and the state of a calendar item, at the price that nothing outside Microsoft's ecosystem can read the result. Dragging a message out of Outlook produces the internal form, which is why the file is unreadable everywhere else.

Opening it here is considerably safer than opening it in your mail client, for two specific reasons. Remote images are never fetched, so the sender is not told that a live person opened the message, which is the standard way a spam list confirms an address is worth attacking. And nothing in the file is executed: the container is walked as bytes to pull out text and attachments, so scripts in the HTML body have no runtime and any attachment stays inert data until you decide to download it. Inspecting a suspicious message before deciding what to do with it is exactly what this page is good for.

Yes, and it is often the real reason people arrive here. Inside the container each attachment sits in its own sub-storage with its filename and its raw bytes; both are read out and offered as ordinary downloads with their original names. This works even when the message body itself cannot be shown, which matters because the usual situation is that a colleague forwarded an invoice or a contract inside a message you cannot open at all.

Read it here when you only need to see it, which is most of the time. Convert it when the file has to go somewhere else: MSG to PDF produces a document for filing, printing or attaching to a claim, and MSG to EML turns it back into standard mail that any client can open and reply to, with its headers and searchable text intact. This page downloads the same PDF as a convenience, so if reading it turns out to be enough, you already have a copy.